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Gabriel PEREZ Valentina VERDEJO Clarissa GONDIM-PORTO Julieta ORLANDO Margarita CARU 《Journal of Zhejiang University. Science. B》2014,15(11):966-978
研究目的：开发具有种属特异性序列特征性扩增区域（SCAR）标记物来监测哈茨木霉在其入侵的试验菌群中的定殖和生长,为哈茨木霉应用于生物防治等生态和生物技术中提供支撑。
创新要点：多种木霉属真菌能与各种微观和宏观的生物有机体建立相互作用。利用这些相互作用,木霉可做为原生种群的入侵物种而用于生物防治。本文通过使用试验菌群为研究模型,利用随机扩增多态性DNA（RAPD）技术和序列特征性扩增区域（SCAR）标记物来监测菌群中哈茨木霉的生长状态。
研究方法：利用随机扩增多态性DNA（RAPD）技术,从16个10聚体引物进行多态性筛选,其中1个引物扩增出对应哈茨木霉的条带。对该条带进行克隆测序,并设计5个20-23聚体引物。成功利用引物对2F2／2R2和2F2／2R3278分别特异性地扩增出哈茨木霉BpTloa菌株278bp和448bp的DNA片段。同时,用这两个引物对14个哈茨木霉菌株和几种不同的真菌菌株进行特异性对照试验,也只成功扩增出哈茨木霉菌株。此外,使用真菌DNA混合物和试验真菌群的DNA为模板,采用实时聚合酶链式反应（PCR）对引物对2F2／2R2进行评估。当仅使用100份SCAR标记物或哈茨木霉仅占整个菌群的0．1％时,仍能检测出哈茨木霉。
重要结论：本研究所建立的SCAR分子标记能有效监测菌群中的哈茨木霉的定殖和生长,具有较高特异性、灵敏度和准确度。 相似文献
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This is an activity for younger learners in which the concepts of relative frequency and probability are explored, illustrating how a creative, non‐transmission teaching approach using bottle tops can enable students to develop their understanding in an engaging fashion and at almost no cost. 相似文献
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This manifesto was first made public in Bogotá, Colombia, on 4 January, 2001 with reference to local creativity and self-esteem. It had considerable regional repercussions. The present is a revised and updated version as a contribution to the current debate on Eurocentrism and its effects in the world. We are Colombian exponents of the natural and the social sciences who want to share our concern for certain types of distortions produced when there is not enough attention given to our contacts and scientific exchanges with colleagues from advanced countries. Our points of view are as follows. 相似文献
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Jacquelyn A. Brown Virginia Pensabene Dmitry A. Markov Vanessa Allwardt M. Diana Neely Mingjian Shi Clayton M. Britt Orlando S. Hoilett Qing Yang Bryson M. Brewer Philip C. Samson Lisa J. McCawley James M. May Donna J. Webb Deyu Li Aaron B. Bowman Ronald S. Reiserer John P. Wikswo 《Biomicrofluidics》2015,9(5)
The blood-brain barrier (BBB) is a critical structure that serves as the gatekeeper between the central nervous system and the rest of the body. It is the responsibility of the BBB to facilitate the entry of required nutrients into the brain and to exclude potentially harmful compounds; however, this complex structure has remained difficult to model faithfully in vitro. Accurate in vitro models are necessary for understanding how the BBB forms and functions, as well as for evaluating drug and toxin penetration across the barrier. Many previous models have failed to support all the cell types involved in the BBB formation and/or lacked the flow-created shear forces needed for mature tight junction formation. To address these issues and to help establish a more faithful in vitro model of the BBB, we have designed and fabricated a microfluidic device that is comprised of both a vascular chamber and a brain chamber separated by a porous membrane. This design allows for cell-to-cell communication between endothelial cells, astrocytes, and pericytes and independent perfusion of both compartments separated by the membrane. This NeuroVascular Unit (NVU) represents approximately one-millionth of the human brain, and hence, has sufficient cell mass to support a breadth of analytical measurements. The NVU has been validated with both fluorescein isothiocyanate (FITC)-dextran diffusion and transendothelial electrical resistance. The NVU has enabled in vitro modeling of the BBB using all human cell types and sampling effluent from both sides of the barrier. 相似文献
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Fabrizio Falchi Claudio Lucchese Salvatore Orlando Raffaele Perego Fausto Rabitti 《Information processing & management》2012
Feature-rich data, such as audio-video recordings, digital images, and results of scientific experiments, nowadays constitute the largest fraction of the massive data sets produced daily in the e-society. Content-based similarity search systems working on such data collections are rapidly growing in importance. Unfortunately, similarity search is in general very expensive and hardly scalable. 相似文献
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Ann-Marie Orlando Elizabeth Klinepeter Megan Foster 《International Journal of Inclusive Education》2016,20(12):1239-1251
Current U.S. legislation calls for students with disabilities to be involved and make progress in general education curriculum. Despite the legislation, students with extensive support needs continue to be segregated from their peers and post-school outcomes remain dismal for this population of students. The purpose of this retrospective study was to explore the perceptions of two students with extensive support needs and their caregivers regarding factors that contributed to their involvement and progress in the general education curriculum and eventual enrolment in four-year, post-secondary institutions in the United States. Findings related to the role of participants’ perceptions of self, participants’ engagement in advocacy roles and activities, and specific human and material supports that both facilitated and acted as barriers to education in the general curriculum emerged as recurrent themes. Limitations of the study and suggestions for future research and practice are presented. 相似文献
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ABSTRACT : Formal human resource diversity programs have experienced rapid growth; yet research on how these initiatives influence organizational effectiveness remains insufficient. This research explores formal diversity programs' influence on organizational effectiveness using universalistic and contingency frameworks. Our findings show that universally, diversity practices strongly and negatively relate to turnover. Organizations with innovative strategies coupled with formal diversity practices had improved productivity and market performance supporting contingency notions. Future research should employ both the universalistic and contingency theories in combination for a more in-depth understanding of construct relationships. 相似文献
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Linda Venticinque Orlando 《Journal of Early Childhood Teacher Education》2013,34(3):247-253
Abstract Based on first hand field notes, I undertook to research the reasons why children interacted or did not interact appropriately with a common emergent literacy experience, the readaloud. I explored the reasons why par‐ents/caregivers may not effectively participate in storybook reading, including reactions of parents/caregivers during four literacy events. I determined that the key to successful literacy experiences were first hand, personal involvement of the children in an active learning experience associated with interactive texts. Here, children were invited to create appropriate actions to accompany the story readings. Interactive texts appear to hold the key to successful early literacy experiences for preschoolers. © 2005 Published by Elsevier Inc. 相似文献
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Joanne Orlando 《Teachers and Teaching》2013,19(4):427-439
In recent years, a significant problem that has manifested in the quest to capitalise on the pedagogical potential of technology in schools is that veteran teachers are unwilling to integrate these resources into their practices. Given that veteran teachers comprise up to 40% of teachers, their lack of use is important. This paper aims to shed light on the issue of detachment by presenting empirically based findings of a five-year, grounded theory examination of the technology practices of a small group of veteran teachers. Data included classroom observations, teacher interviews and document analysis of teacher and school planning documentation, student focus groups, interviews with teaching colleagues and key school technology personnel observation. Analysis included the application of the teachers’ data to a framework of dilemmas teachers encounter when expected to change their practice. In using this process, change fatigue and knowledge insecurity (brought about by cultural and political changes to their contexts) were prominent factors which contributed to the teachers’ lack of technology use. Identifying their challenges opened scrutiny to the myriad of factors they drew on when making decisions about how and whether to use technology in their practice. The longitudinal analysis of the data showed that as these dilemmas alleviated, the teachers became more committed to educational technology. The findings inform how we can move forward from the issue of veteran teachers’ lack of use of technology to how to support this group in the development of their practices. In particular, the need for a re-imagining of professional learning to one which focuses on reshaping cultural and political aspects of technology practices. This includes changes to the management of technology-related policy changes as well as facilitating learning communities that promote a valuing and sharing of relevant knowledge amongst teachers and students. 相似文献